Empyema necessitans is a rare complication of empyema with extension of the fluid collection and infection to the subcutaneous soft tissue. The most common cause of empyema necessitans is Mycobacterial infection, as in our patient. Less common causes include actinomyces, streptococcus, and staphylococcus infection.

This case also demonstrates erosion of an intercostal artery as a complication of empyema necessitans The patient was subsequently treated with arterial embolisation.